Antenna construction



May 24, 1932. BETHENOD 1,860,128

ANTENNA CONSTRUCTION Filed March 2, 1927 INVENTOR JOSEPH BETHENOD Evy/ML ATT RNEY Patented May 24, 1932 omransmrss nsane v JosEPHnnTHENon, or rARrsrRANon ANTENNA CONSTRUCTION Application filed March 2, 1927, Serial No. 171,993, and in France March 9, 1926.

An object of this invention is to provide a method for neutralizing the radiation from a portion of an antenna. A further object is to provide an antenna adapted for short wave lengths and one in which the length of the transmitted wave may be easily varied.

A still further object is to provide an antenna in which the effective radiation is confined to a portion only thereof. A further object is to provide a screen to neutralize the radiation from a desired portion of an an tenna. A still further object of the invention is to provide novel means for varying the length of an antenna.

The invention will be better understood by reference to the accompanying drawing and the following specification covering one embodiment of the arrangement by way of example.

An antenna consists of a suitable conductor A, B C, connected with ground at A. This antenna is excited by a high frequency generator in any desired and known manner, for instance by means of magnetic coupling with an inductance coil, marked D, arranged in series with the antenna.

In parts AB of the aerial located inside.

the station or in the immediate neighborhood thereof according to the invention there is provided a screen EF which may consist of a simple conductor identical to the part AB in question arranged parallel thereto but at suficient proximity. For further similarity, screen E-F may comprise an inductance coil G, inductances G and D being then made adjustable if desired. The screen EF may be grounded at E.

Inductances G and D are loosely cou pled and so wound that they oppose eachthe left being arbitrary, but also capable of assuming as its limiting position, one that will fall on the prolongation of thevertical "portion A.B. At C the antenna is secured to an 1nsulat-orH whichitself is" in turn attached to a wire or strand 1; Inorder to lnsure radiationof the antenna" at .maximum eficiency, length'B-C should preferably be chosen of a length equal to a whole number integer ormultiple) of half wave lengths. If the equipment is intended .for working on various wave lengths, according to this invention, the lengthof portion BG is made adjustable tothe desired length of wave bythe aid of any suitable cuits of the antennais insured by a mobile connection system, for instance, a brush or contact device P in frictional engagement with a ring'carriedon the drum, the said bgi sh P beingjunited with the inductance The; inclination of portion B C with respect to the horizontal may be varied by any convenient means The means shown includes a cable or strand R in one end of which pulley J is pivoted'the other end of the cable being attached'to a wincl1 S-on which it may be wound, two intermediate pulleys T serving to 'guide' andsupport Y the cable R; The present inventiongas will be readily understood is capable of -a great number of modifications, in construction or in detail. For example, a plurality of antenna arrangements of the same kind conveniently orientat-ed or directed" with reference to one another, may be combinedin the samestation with the end-in View of insuring dir'e ctional 7 features or else to insure multiple operation.

purposes, obviouslyby varying the length of BC the Wave length of the transmitted Wave may be varied.

While I have herein shown the preferred form of the invention, I am aware that various changes in arrangement and details of construction may bemade without departing from the spirit thereof and I do not limit myself to. theform shown.

What I claim is 2 1. An antenna system comprisinga vertical non-radiatingportion, a radiating porvertical antenna Whose height is equal to that of the vertical part of the first antenna, and

coupling means between the vertical parts of these antennae for inducing in each one thereof currents phase.

In Witness whereof I hereunto afii my signature.

JOSEPH BETHENOD.

respectively opposed in tion, means for adjusting the radiating portion as to length and means for adjusting the radiating portion as to angle of inclination. 2. An antenna system comprising a vertical portion of constant length, a second portion adjustable both as to length and to horizontal angular displacement, and means for neutralizing the radiation from the vertical portion.

3. An antenna system comprising a vertical portion of constant length and a second portion adjustable both as to length and to horizontal angular displacement, and means for neutralizing the radiation from the vertical portion, said means including ascreening antenna adjacent to said vertical portion and equal in length thereto.

4. An antenna system comprising a vertical portion constant in length, a second adjustable radiating portion, an inductance coil 'in said vertical portion, a source of high frequency currents coupled to said inductance coil and a vertical conductor equal in length to said vertical portion and having an in ductance coil loosely coupled to said first mentioned coil, the arrangement being such that the currents in said vertical conductor and said verticalantennaportion are opposite in phase whereby the radiation from the latter is effectively neutralized.

"5. An antenna system comprising a vertical portion of constant length and a second adjustable portion, means for varying the length of said latter portion, and additional means for adjusting its angle of inclination.

6. An antenna system comprising anantenna having a vertical part and'an inclined part, means for regulating the length of the said inclined part, means for regulating the inclination of the said inclined part, another 

